BAGHDAD, Iraq (CNN) -- Former Iraqi exile leader Ahmed Chalabi and his nephew, the head of the war crimes tribunal, say they will return to Iraq to face what they have called "ridiculous" criminal charges.

Ahmed Chalabi, the head of the Iraqi National Congress (INC) and a member of the now-dissolved Iraqi Governing Council, has been charged with counterfeiting, Chief Investigative Judge Zuhayr al-Maliky told the U.S.-backed broadcaster Radio Sawa.

Salem Chalabi faces an arrest warrant in connection with a murder charge.

"An arrest warrant has been issued by the Central Criminal Court ... based upon a complaint filed by an Iraqi citizen. The investigation is ongoing and the subject is the crime of murder," Maliky said.

Both men were out of the country Sunday evening. But in interviews with CNN, they professed their innocence and said they plan to return to Iraq to contest the charges.

"I'm going back to confront those lies," Ahmed Chalabi, in Tehran, told CNN.

In London, Salem Chalabi called the charge against him "ridiculous."

"I have no recollection of ever meeting that person," he said. "Apparently I threatened somebody who subsequently was killed."

He said the charge almost certainly had "something to do with trying to discredit" the war crimes tribunal.

But Salem Chalabi stopped short of attributing that motive to Chief Investigative Judge Zuhayr al-Maliky.

"I don't know if he wants to do that ... but Baathists are currently unhappy about the existence of the tribunal and want to try to discredit the whole procedure," Chalabi said from London, where he was when the warrant was issued.

"There are a lot of people in Iraq who want to destabilize the tribunal, and I suspect that some of them are linked somehow to the government," he said.

"There are many Baathists in government now."

Ahmed Chalabi was a Pentagon favorite before the 2003 invasion of Iraq, and the INC received more than $27 million in U.S. funds.

But in May, Iraqi police and U.S. troops raided his home and office, and U.S. officials accused him of passing closely-held American secrets to Iran -- allegations the former exile leader denies.

In a written statement, he said he collected samples of counterfeit money while chairman of the Iraqi Governing Council's finance committee, which also oversaw the country's central bank.

"It is these samples that Iraqi police found when they illegally raided our offices last May," he said.

"The idea that I was involved in counterfeiting is ridiculous and the charges are being made for political purposes."

'Set up'

Both Chalabis said Maliky is a former member of Saddam Hussein's Baath Party who hope to derail the Iraqi special tribunal set up to try the former leader.

"Without a doubt, I'm being set up," Ahmed Chalabi said. Salem Chalabi said the charges were brought "to discredit the family and discredit the tribunal."

"I intend to return and address the charges in due course," he said.

"I also feel that the court in question has an ulterior motive, and so I'm going to request an investigation into several things about this charge itself."

One of Chalabi's remaining American supporters, Richard Perle, called Maliky a "rogue, out-of-control judge."

"He's systematically issued warrants against the INC and other members of the INC, and finally he's done it with respect to Ahmed Chalabi," said Perle, a member of the Pentagon's Defense Policy Board and a former Reagan administration official.

"It's Saddam Hussein's style of justice, and it's appalling."

Salem Chalabi said minutes of a meeting he attended on the day of the death support his case that he could not have been responsible.

As Saddam's government fell in April 2003, the U.S. military flew Ahmed Chalabi into Iraq at the head of a militia dubbed the "Free Iraqi Forces."

Soon afterward, he was named to the Iraqi Governing Council under the U.S.-led occupation.

But when the Americans began to search for Saddam's feared arsenal of weapons of mass destruction, much of the intelligence the INC supplied about the suspected stockpiles failed to pan out.

An exile who lived abroad for more than four decades, Chalabi was convicted in absentia of bank fraud in 1992 by a military court in Jordan, where he had founded a bank that failed. He says the charges were politically motivated.

After the raid on his office, Chalabi broke ties with the U.S.-backed occupation authority. But his years in exile and close ties to the United States have left him struggling to gain a political foothold in his home country.

The White House declined comment Sunday. A spokesperson told CNN the charges are "a matter in the hands of the Iraqi authorities and they will resolve it."